Granted Patent
Utility
US 4,725,007 · App. 06/816,696
Apparatus for pulping high consistency paper making stock
Inventor:
David E. Chupka
Patented Case
View Patent ↗
Granted: Feb 16, 1988
Filed: Jan 6, 1986
Inventor
David E. Chupka
Assignee (at issue)
Black Clawson Company, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.